JPH11311594A - Rotary viscometer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary viscometer that enables reading of an indication for a plurality of number of times during one rotation of a drive shaft. SOLUTION: A viscosity indication detection device of a rotary viscometer includes a rotary main shaft-shielding disc 35 set at a rotary main shaft 25, a torque detection shaft-shielding disc 36 set at an upper end of a torque detection shaft 29, and optical detectors 200 and 210 each comprising a light-emitting diode 16 for detecting passing of a light transmission slit formed in the shielding disc 35, 36 and a photodetecting element phototransistor 17. The shielding discs 35, 36 are the same ones having light transmission slits 300 formed at a plurality of positions equally divided at an entire circumference.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an economical method of converting the result of viscosity measurement by a rotary viscometer into an electric signal. The present invention relates to improvement of a rotary viscometer using a transit time pulse counting signal conversion method.

[0002]

2. Description of the Related Art In a chemical industry, a synthetic science industry, a pharmaceutical industry, a food industry, an oil and fat industry, a paint industry, a textile industry, a cosmetics industry, and the like, a liquid material is used as a main raw material or an auxiliary raw material. 2. Description of the Related Art Various rotary viscometers are widely used for reaction control and quality control when a product is manufactured by processing.

The measurement principle of this rotary viscometer will be described with reference to FIG. FIG. 1 illustrates the above-described application.
The measurement principle of a rotary viscometer (for example, a B-type viscometer) that is currently most frequently used will be described.

As shown in FIG. 1, a conventional viscometer mainly has a variable speed motor 1 as a rotary driving source.
And an output shaft 2 connected to the variable speed motor 1 and a scale disk 3 engraved with an angle scale 3a 'through which the output shaft 2 is fixed. Further, the viscometer includes a spring 4 attached to the lower end 2 'of the output shaft 2, a rotor stem 5 attached to the lower end of the spring 4, and a measured object attached to the lower end of the rotor stem 5. It includes a cylindrical rotor 7 immersed in the liquid 6 and a U-shaped pointer 8 provided on the upper end of the rotor stem 5. Here, the U-shaped pointer 8
Is mounted so that it can point to the angle scale 3a 'on the scale disk 3.

In this conventional viscometer, the cylindrical rotor 7 is
It is immersed in the liquid to be measured 6 whose viscosity is to be measured. In this state, when the variable speed motor 1 is rotated at a constant speed, the spring 4 is twisted to an angle balanced with the viscosity torque of the liquid 6 to be measured generated in the cylindrical rotor 7. Spring 4 at this time
Since the torsional angle of the liquid 6 and the viscosity of the liquid 6 to be measured are in a proportional relationship, the viscosity of the liquid 6 to be measured is obtained by reading the scale plate finger 3a 'indicated by the tip 8a of the U-shaped pointer 8. be able to.

Here, in order to obtain a measured value, the finger index 3a 'on the scale plate 3 must be read while the scale plate 3 is rotating. Generally, the upper limit of the number of rotations of the scale plate 3 is about 60 rpm, so that it is not impossible to visually read the finger power, but it is extremely inconvenient, and there has been a need for improvement since ancient times. Further, recently, there have been demands for functions related to automation, such as remote control of a viscometer, automatic measurement, and automatic recording of measurement results. Therefore, it is becoming impossible to cope with the conventional visual reading of the pointer finger.

For this reason, the pointer finger 3 on the scale disk 3
a ′, that is, the torsion angle of the spring 4 is transmitted as an electric signal using a signal converter that directly converts the angle into an electric signal, such as a rotary differential transformer or a rotary encoder, Viscometers of an automatic reading system for displaying or recording an index by receiving this signal with a suitable receiver have already been put to practical use in expensive rotary viscometers such as rheometers.

However, these signal converters have a complicated structure and are expensive in cost, and have a drawback that they cannot be used for a low-cost on-site rotary viscometer.

In view of such a situation, the present inventor has applied for an invention relating to a viscometer provided with an automatic reading device for a scale plate as shown in FIG. 2 (Japanese Patent Application No. 49-1).
No. 11236). The automatic reading device listed here is based on the principle of measuring the passing time difference between the pointer rotating in the viscosity measurement state and the zero point of the scale disk, and the operation is stable and cost effective. Due to its low cost, it is still widely used in relatively inexpensive rotary viscometers (for example, E-type viscometers).

FIG. 2 shows the structure of the reader according to the prior art. This reading device is connected to a variable speed motor 1 and driven to rotate, a scale plate 3 attached to the drive shaft 12, and connected to a rotor 7. For the resistance torque, a spiral spring type torque spring (not shown) has a torque detection shaft 15 for detecting a twist angle generated by balancing, and a pointer 8 fixed to the torque detection shaft 15.

Further, this reading apparatus includes two sets of optical detectors 200 and 210 each composed of a light emitting diode 16 and a phototransistor 17, a light shielding piece 3a provided on the lower surface of the scale plate 3, and a pointer 8. And a light shielding piece 8a fixedly provided.

The optical detector 200 has a light shielding piece 3a provided on the lower surface of the scale plate 3, and the optical detector 210 has
A light-shielding piece 8a fixed to the pointer 8 detects light-shielding when passing through a gap between the light-emitting diode 16 and the photo-transistor 17 together with rotation of the drive shaft 12 and the torque detection shaft 15 of the viscometer.

Furthermore, in this reading device, the rotor 7
When the viscometer is operating in a state where the viscous resistance torque of the liquid 6 to be measured is not applied to the torque detection shaft 15 via the torque detector 15, the optical detectors 200 and 210 simultaneously operate the respective light shielding pieces 3a and 8a. Positioned and mounted to detect passage.

If the relative positions of the optical detectors 200 and 210 are determined in advance as described above, when the viscosity is measured by immersing the rotor 7 in the liquid 6 to be measured, the optical detector 200 is used.
And 210 detect the passage of the light shielding pieces 3a and 8a, respectively, corresponding to the torsional angles in rotation of the drive shaft 12 and the torque detection shaft 15.

The torsional angular displacement of the torque spring caused by the viscous resistance torque of the rotor 7 is, as shown in the upper two stages of FIG. 3, a pulse signal from the phototransistor 16 of each of the optical detectors 200 and 210. It appears as the phase difference θ of the transmitted pulse signal.

Accordingly, in order to automatically read the pointer index of the viscometer, for example, as shown in the lower part of FIG. 3, signals from two phototransistors 16 are used as gate signals.
In response to the rotation speed of the drive shaft 12 output during that time,
A clock pulse having a predetermined oscillation frequency is counted.

If the transmission frequency of the pulse is related to the rotation speed of the drive shaft 12 in advance, the counted number of pulses corresponds to the torsion angle. The automatic reading equivalent to the reading of the pointer finger can be performed.

This prior art is a method in which the difference between the transit time between the pointer 8 and the scale disk 3 is counted by a clock pulse to make the measured value correspond to the scale index.
In addition, there is a feature of stable operation at low cost.

[0019]

However, in the prior art, one rotation of the scale plate 3 of the rotary viscometer per rotation.
The reading can be performed only once. Therefore, when the viscometer is operated at a low rotation speed such as 0.5 rpm, for example, in the worst case, the first measurement data cannot be obtained unless the user has to wait two minutes after the start of operation. Furthermore, after that, 2
There is an inconvenience that the finger reading is performed only once per minute.

Further, in the case of such a signal conversion system having a low data density, for the purpose of measurement requiring a viscosity measurement value immediately after the start of viscosity measurement, for example, a two-liquid curing reaction speed is high. When the curing time characteristic of a mixed adhesive or the like is measured as a change in viscosity, there is a problem that the measurement cannot be performed at all.

It is an object of the present invention to provide a rotary viscometer capable of reading a finger a plurality of times during one rotation of a drive shaft of the viscometer.

[0022]

SUMMARY OF THE INVENTION The object of the present invention is to provide a rotary viscometer for measuring the viscosity of a liquid to be measured by immersing a rotating rotor in the liquid to be measured. A drive source, a drive shaft driven by the rotary drive source, an elastic member for elastically connecting the drive shaft and the torque detection shaft, and a rotation of the drive shaft in a predetermined angle unit of 180 ° or less, 1st output detection signal
Rotation detection means, a second rotation detection means for outputting a detection signal for the rotation of the torque detection shaft in a predetermined angle unit of 180 ° or less, and an output signal from the first and second rotation detection means. Respectively, a time difference detecting means for detecting a time interval between them, and a finger reading means for calculating a viscosity finger corresponding to a rotational phase difference between the drive shaft and the torque detection shaft from the detected time interval. It can be achieved by a rotary viscometer characterized by having

[0023]

In the rotary viscometer to which the present invention is applied, the drive shaft is rotated at a constant speed by the rotary drive source while the rotor is immersed in the liquid to be measured for viscosity. Then, the elastic member is twisted to an angle at which the viscous torque of the liquid to be measured generated in the rotor and the elastic force of the elastic member connecting the torque detection shaft and the drive shaft connected to the rotor are balanced. A phase difference occurs in the rotation of the shaft. At this time, since the twist angle of the elastic member and the viscosity of the liquid to be measured are in a proportional relationship, the viscosity of the liquid to be measured can be obtained by detecting the viscosity index corresponding to the twist angle.

In the present invention, the rotational phase difference corresponding to the viscosity index is converted into a signal as described below, and the viscosity index is automatically detected.

When the drive shaft rotates, the first rotation detecting means outputs a signal for each predetermined angle unit. Also,
At the same time, the second rotation detecting means also outputs a signal for each rotation of the torque detection shaft for each predetermined angle unit. Here, since the angle unit is 180 ° or less, the signal is output two or more times during one rotation of the drive shaft or the torque detection shaft. In addition, since a phase difference corresponding to the torsion angle occurs in the rotation between the drive shaft and the torque detection shaft, these two signals are output with a time lag. The time difference detecting means detects the time interval between the two signals output by the first and second rotation detecting means a plurality of times during one rotation. The finger degree reading means calculates the viscosity finger degree corresponding to the twist angle from the detected time interval each time the time interval is input from the time difference detection means.

Therefore, according to the present invention, the viscosity index can be calculated a plurality of times during one rotation of the drive shaft or the torque detection shaft according to a predetermined angle unit of 180 ° or less.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a viscometer to which the present invention is applied will be described with reference to FIGS. In the following description, the same reference numerals in the drawings denote the same parts.

This embodiment measures the viscosity according to the measurement principle described with reference to FIG. 1, and has a functional block shown in FIG.

In this embodiment, as shown in FIG. 9, a cylindrical rotor 7 for detecting the viscosity of the liquid 6 to be measured, a drive mechanism 110 as a rotary drive source, a torque detecting shaft connected to the cylindrical rotor 7 and A rotation mechanism 100 having a drive shaft that is rotationally driven by the drive mechanism 110, a phase difference detection mechanism 120 that converts and detects a rotation phase difference between two axes included in the rotation mechanism 100 into an electric signal, and a phase difference detection mechanism 120
A controller 130 for calculating the viscosity index of the liquid 6 to be measured and controlling the driving mechanism 110 using the signal regarding the phase difference output from
And a rotation number setting unit 150 for setting various constants such as the rotation number of the driving source in the driving mechanism 110.

The cylindrical rotor 7 is used to detect the viscosity.
It is immersed in the liquid 6 to be measured. Here, the cylindrical rotor 7 is used, but a conical rotor or the like may be used.

The structure of the driving mechanism 110 will be described with reference to FIG. FIG. 6 is a side view of the present embodiment, showing an outline of the internal structure of a drive system mounted on the upper part.

As shown in FIG. 6, the driving mechanism 110
A driving pulse motor 21, a driving timing pulley 22 attached to an output shaft thereof, a timing belt 24 hung on the pulley 22, and a driving shaft (hereinafter, referred to as a rotating main shaft) driven to rotate by the timing belt 24. ) 25 and a pulley 23 attached to the pulley 23. Further, although not shown, the driving mechanism 110
A power supply device for the pulse motor 21 is included.

As the driving pulse motor 21, a pulse motor having a small basic step angle is used in order to ensure smooth rotation, which is important as a viscometer. Furthermore, a multi-step speed change can be electronically performed by using a micro-step drive system in which the number of divisions is appropriately increased.

The structure of the rotation mechanism 100 will be described with reference to FIG. FIG. 7 is a schematic sectional view of the internal structure of the viscometer of the present embodiment shown in FIG. 6 as viewed from the front.

As shown in FIG. 7, the rotating mechanism 100 has
A hollow rotary spindle 25 driven by a pulse motor 21 (see FIG. 6) via a pulley 23 and the like; bearings 26a and 26b rotatably supporting the rotary spindle 25 at two upper and lower ends thereof; A first U-shaped connecting member 27 attached to the lowermost end of the rotating main shaft 25;

The rotating mechanism 100 further includes a jewel bearing 28 provided on the lower side 27a of the first U-shaped connecting member 27, and a pivot 3 supported by the jewel bearing 28.
0, a torque detecting shaft 29 having a pivot 30 implanted at its lower end, a second U-shaped connecting member 27b connected to the torque detecting shaft 29 above the pivot 30,
And a torque detecting shaft connecting member 29a provided below the U-shaped connecting member 27b and connected to the cylindrical rotor 7 via the rotor stem 5.

Here, the torque detecting shaft 29 penetrates inside the hollow rotary main shaft 25 without contacting each other and extends upward.

The configuration of the phase difference detection mechanism 120 of this embodiment will be described with reference to FIG. FIG. 8 shows the phase difference detection mechanism 1.
FIG. 2 is a schematic view of the present embodiment, including parts directly related to 20.

The phase difference detecting mechanism 120 has a U-shaped arm member 31 attached to the upper end of the hollow rotary main shaft 25 and an upper side 31a of the U-shaped arm member 31 provided coaxially with the rotary main shaft 25. A cup-shaped steady rest 32 having a small hole 32a on the bottom surface, a pin 33 inserted through the small hole 32a and implanted in the upper end surface 29b of the torque detecting shaft 29, and attached near the upper end of the torque detecting shaft 29. And a torque spring 34 in the form of a spiral spring.

Here, the outer peripheral winding end of the torque spring 34 is locked to the inside 31 b of the U-shaped arm member 31.
In addition, the steady rest 32 and the pin 33 function as a bearing for stopping the radial swing of the torque detecting shaft 29.

Further, the phase difference detection mechanism 120 has a rotary spindle shielding disk 35 attached above the rotary spindle 25 and below the U-shaped arm member 31, and a pin implanted at the upper end of the torque detection shaft 29. It includes a torque detection shaft shielding disk 36 attached to the disk 33, and optical detectors 200 and 210 provided on the respective shielding disks 35 and 36 for detecting passage of a slit described below.

Each of the optical detectors 200 and 210 comprises a light emitting diode 16, a light receiving element phototransistor 17, and a power supply control device (not shown) necessary for them. Light emitting diode 16 and light receiving element photo
The transistor 17 is a shield disk 35, 36, respectively.
Are provided facing each other up and down.

The shielding disks 35 and 36 are the same, and a slit 300 is provided at a position where the entire circumference is equally divided as shown in FIG. In this embodiment, the shielding disk 3
It is assumed that slits for transmitting light are provided at positions 5 and 36 at every 72 ° where 360 ° is divided into five equal parts. of course,
The number of divisions in the shielding disks 35 and 36, that is, the number of slits is not limited to this.

Further, instead of the light transmission slit 300,
As an index, a reflector that reflects light, a small piece of a magnetic member, or the like can be used. However, in this case, it is necessary to use a detector for each index according to the characteristics of each index.

Instead of using the shielding disks 35 and 36, an index may be directly attached to the shaft surface of the rotating main shaft 25 and the torque detecting shaft 29, or a cylinder fixed to each shaft may be used.

Shielding disks 35 and 36 and optical detector 2
00 and 210 respectively correspond to the cylindrical rotor 7
Is rotating with no load, the optical detector 2
00 detects the passage of one of the light transmitting slits 300 of the disk 35 and the optical detector 210
The position at which the passage through any one of the light transmission slits 300 is detected is the same as the position at which the passage is detected.

The controller 130 of this embodiment has
As shown in the figure, a clock circuit 131 for generating a clock pulse of a predetermined frequency, a counter 133 for counting inputted pulses, and optical detectors 200 and 21
A gate circuit 132 that controls the output of an input clock pulse using the passage detection pulse from 0 as a gate signal.
And the number of pulses calculated by the counter and the pulse motor 21
And a pulse motor driver 135 for calculating the viscosity fingeriness of the liquid 6 to be measured from the rotation speed of the liquid.

Here, the pulse motor driver 135 is
A motor drive signal corresponding to the designated number of revolutions is given to the pulse motor 21 of the drive mechanism 110 by the signal of the number of revolutions setter 150 to control the rotational motion. In addition, the clock circuit 131 generates a clock pulse having an oscillation frequency corresponding to the rotation speed and given by the following equation 2 by the same signal as the rotation speed designation signal sent to the pulse motor 21.

As shown in FIG. 9, the display 140 displays the viscosity index of the liquid to be measured outputted from the controller 130. Further, the viscosity index output from the controller 130 may be directly output as data for external viscosity calculation. According to the present embodiment having the above-described structure, it is possible to detect the viscosity index five times during substantially one rotation of the cylindrical rotor 7.
However, in the specification of the present embodiment, it is required that the viscosity measurement data obtained by the viscometer of the present invention be the same as the viscosity measurement data obtained by the conventional viscometer, that is, the continuity of measurement be ensured. . Therefore, the structural specifications necessary to ensure this continuity will be examined.

As in this embodiment, almost one cylinder rotor 7
In order to allow five readings during rotation, the light transmission slit 30 is divided every 72 ° by dividing 360 ° of the shielding plate into five.
In addition to providing 0, the spring constant of the torque spring 34 is considered to match the condition of the spring constant used in the conventional viscometer. Need to be reviewed.

That is, in the conventional viscometer, the spring constant of the torque spring 34 is related to generate a full-scale torque with respect to a twist angle of 315 °. Therefore, in the case of 5 divisions and 72 ° in this embodiment,
It is necessary to change the spring constant of the torque spring 34 to 5.25 (= 315 ° / 60 °) times the conventional spring constant so that a full-scale torque is generated when the torsion angle is 60 °.

The reason why 60 ° corresponds to the twist angle at which full-scale torque is generated without using the entire 72 ° angle range is that an angle margin is required for the viscometer adjustment operation. Of course, it is sufficiently possible to reduce the angle of the margin to 65 ° or 70 ° as the full-scale torque, except for the difficulty of the adjusting operation at the time of adjusting the viscometer due to the narrow margin area.

Further, the frequency of the clock pulse is determined by the scale division specification of the scale plate 3 (see FIG. 2) of the conventional B-type or E-type viscometer. 100 scales are engraved as a scale. Therefore, the oscillation frequency f ₀ of the clock pulse
Is to read 1 scale in this case to 1/10,

[0054]

(Equation 1)

Can be expressed as follows. Here, n is the rotational speed of the viscometer (rpm).

Therefore, considering the data compatibility with such a conventional viscometer, in the present embodiment, when the transmission frequency of the clock circuit 131 is selected from the range of 60 ° in the angle range of the full-scale torque. It is necessary to determine that this angle of 60 ° corresponds to 100% of the full scale of the finger index as a viscometer. In this case, the clock frequency is

[0057]

(Equation 2)

Must be used. Here, n is the rotational speed of the viscometer (rpm).

The operation of this embodiment will be described below with reference to FIGS.

In the rotary viscometer of this embodiment, as shown in FIG. 6, the cylindrical rotor 7 is immersed in a liquid to be measured (not shown) whose viscosity is to be measured. In that state, pulse motor 2
When 1 is rotated at a constant speed, the rotating main shaft 25 is driven via the pulleys 22 and 23 and the timing belt 24.

When the rotary main shaft 25 rotates, as shown in FIG. 8, the rotary main shaft 25, the torque detection shaft 29 connected by the torque spring 34, and the cylindrical rotor 7 rotate. Here, due to the viscous torque of the liquid to be measured, the torque spring 34 is moved to an angle that balances the viscous torque.
Is twisted. At this time, the torsion angle of the torque spring 34 and the viscosity of the liquid to be measured are in a proportional relationship.

In the present invention, this twist angle is interposed between the shielding disks 35 and 36 connected to the rotating main shaft 25 and the torque detecting shaft 29, respectively, and an optical detector for detecting the passage through the light transmitting slit 300. 200 and 210.

The rotating main shaft 25 and the torque detecting shaft 29 are
When each rotates, the shielding disks 35 and 36 rotate.
According to the rotation of the disks 35, 36, the optical detectors 200, 210 each composed of the light emitting diode 16 and the phototransistor 17 arranged vertically with the light emitting axis and the light receiving axis interposed therebetween are formed by a light transmitting slit. Each time 300 passes through each detection point, it emits a pulse signal.

Here, a state in which the cylindrical rotor 7 is idled in the air (a completely unloaded state in which no load torque is applied to the cylindrical rotor 7), that is, a state in which the torque spring 34 is rotating without being subjected to torsion. FIG. 5 shows a time chart of the transmission pulses of the optical detectors 200 and 210 provided on the rotary shaft shielding disk 35 and the torque detection shaft shielding disk 36 in FIG.

In this embodiment, as shown in FIG.
In the no-load state, the light transmission slits 300 (A, BE) of the drive shaft shielding disk 35 and the light transmission slits 300 (A ′,
B'-E ') are the respective optical detectors 200, 21
0 at the same time, so that any light transmission slits 300 are arranged in such a way that no transit time difference occurs. When the viscosity is measured using this embodiment, that is, when the viscous torque is applied to the cylindrical rotor 7 and the torque spring 34 rotates while being twisted, the outputs of the optical detectors 200 and 210 are as shown in FIG. Top 2
It is as shown in the column. Here, the time difference between the passage of the light transmission slit 300 of the rotary spindle blocking disk 35 and the passage of the light transmission slit 300 of the torque detection shaft shielding disk 36 is the same as that of the conventional technology. In the same manner as described in the section, the torque spring 34 is proportional to the torsion angle.

However, unlike the prior art, in the viscometer of the present invention, the number of times corresponding to the number of light transmitting slits 300 obtained by dividing 360 ° of the shielding plate per one rotation of the cylindrical rotor 7 of the viscometer is obtained. (5 times in the embodiment).

The outputs from the optical detectors 200 and 210 are input as a gate signal to a gate circuit 132 shown in FIG. In this gate circuit 132,
Is received from the clock circuit 131 and the clock pulse output to the counter 133 is controlled by a gate signal. Specifically, as shown in FIG.
First, at the time when the output of the passage detection signal of each light transmission slit 300 from the optical detector 200 (the uppermost stage in FIG. 10, the pulses A and BE) is received, the clock circuit 131
The output of the clock pulse received from the counter 133 to the counter 133 is started. Next, the gate circuit 132 outputs an output signal from the optical detector 210 indicating the detection of the passage of the light transmission slit 300 (middle stage in FIG. 10, pulses A ′, B ′ to E ′).
, The output of the clock pulse is stopped (at the bottom of FIG. 10).

The counter 133 counts a group of clock pulses output as described above. Here, the clock pulse has a fixed relationship with the rotation speed of the drive shaft as shown in Expression 2. Therefore, using this relationship,
The finger degree calculation unit 134 can easily calculate the twist angle or the viscosity finger degree from the count value and display the twist angle or the viscosity finger degree on the display 140.

In the present embodiment, the fingeriness calculation unit 134 calculates the viscosity fingeriness. However, it is also possible to finally calculate the viscosity based on the data of the viscosity finger degree in the finger degree calculation unit 134 and display the result on the display 140.

As described above, in the conventional viscometer,
While the scale reading could be performed only once per rotation of the scale plate, in the present embodiment, the viscosity index is increased by the number of light transmission slits 300 dividing the entire circumference per substantially rotation of the cylindrical rotor 7. Can be read. Therefore, if the number of light transmission slits is N, the time required for reading and displaying the first measured value and the time required for reading and displaying the measured value thereafter are reduced to 1 / N of the conventional viscometer. be able to. Even when the viscosity of the sample liquid changes in a short time, the number of measurements during one rotation of the viscometer can be measured at a density several times higher than that of the conventional viscometer. Can be enough.

[0071]

According to the present invention, in the viscosity measurement, the number of times of measurement during one rotation of the rotor for measuring the viscosity can be increased several times as compared with the conventional viscometer. Therefore, the time until the data is displayed at the low-speed rotation can be reduced to a fraction of that in the related art.

[Brief description of the drawings]

FIG. 1 is a diagram showing the principle of a conventional rotary viscometer.

FIG. 2 is a view for explaining a pointer finger reading unit of a rotary viscometer according to a conventional technique.

FIG. 3 is a diagram showing outputs from optical detectors 200 and 210.

FIG. 4 is a view showing a shielding disk used in the embodiment of FIG. 9 to which the present invention is applied.

FIG. 5 is a diagram showing timings of output signals of two optical detectors in an unloaded state according to an embodiment to which the present invention is applied.

FIG. 6 is a side view of an embodiment to which the present invention is applied, showing a schematic configuration of a driving mechanism provided at an upper portion.

FIG. 7 is a front sectional view of the embodiment of FIG. 6, showing a schematic configuration of a rotation mechanism.

FIG. 8 is a diagram illustrating a schematic configuration of a phase difference detection mechanism according to the embodiment of FIG. 6;

FIG. 9 is a functional block diagram of an embodiment to which the present invention is applied.

FIG. 10 shows a state in which the viscosity is measured in the embodiment of FIG.
The figure which shows the timing of the output signal of two optical detectors.

[Explanation of symbols]

1: Variable speed motor, 2: Output shaft, 3: Scale disk, 3:
a ': Angle scale, 3a light shielding piece, 4 ... spring, 5 ...
Rotor stem, 6 ... sample liquid, 7: cylindrical rotor, 8: U-shaped pointer, 8a: light shielding piece, 12: drive shaft, 15: torque detection shaft, 16: light emitting diode, 17: phototransistor, 21 ... Driving pulse motor, 22, 23 pulley, 24 timing belt, 25 rotating spindle, 26a
26b: bearing, 27: first U-shaped connecting member,
27b: first U-shaped connecting member, 28: jewel bearing,
29: torque detection shaft, 29a: torque detection shaft connecting member,
Reference numeral 30: pivot, 31: U-shaped arm member, 32: steady rest, 33: pin, 34: torque spring, 35:
Rotating main shaft shielding disk, 36 ... Torque detection shaft shielding disk, 10
0: rotation mechanism, 110: drive mechanism, 120: phase difference detection mechanism, 130: controller, 131: clock circuit,
132 gate circuit, 133 counter, 134 finger calculation unit, 140 display unit, 150 rotation speed setting unit, 20
0, 210: Optical detector, 300: Light transmission slit.

Claims (6)

[Claims] 1. A rotary viscometer for measuring the viscosity of a liquid to be measured by immersing a rotating rotor in the liquid to be measured, comprising: a torque detection shaft connected to the rotor; a rotary drive source; A drive shaft to be driven, an elastic member for elastically connecting the drive shaft and the torque detection shaft, and a first signal for outputting a detection signal in a predetermined angle unit of 180 ° or less for rotation of the drive shaft. Rotation detection means, second rotation detection means for outputting a detection signal for the rotation of the torque detection shaft in a predetermined angle unit of 180 ° or less, and output signals from the first and second rotation detection means. A time difference detecting means for capturing each of them and detecting a time interval between them; and a finger reading means for calculating a viscosity finger corresponding to a rotational phase difference between the drive shaft and the torque detection shaft from the detected time intervals. Rotational viscometer, wherein Rukoto. 2. The first rotating body according to claim 1, wherein the first rotation detecting means is fixed to the drive shaft and has an index provided at a position obtained by equally dividing the entire circumference into a plurality of parts. A first passage detection mechanism that is provided in the vicinity of the rotation trajectory of the body index and outputs a signal each time the index passes through a predetermined position; A second rotating body fixed to the detection shaft and having the same number of divisions as the first rotating body and provided with indices at positions obtained by equally dividing the entire circumference into a plurality of parts, and a second rotating body provided near the rotation path of the index of the second rotating body. The index has a second passage detection mechanism that outputs a signal each time it passes through a predetermined position, and the time difference detection unit receives an output signal from the first passage detection mechanism, Further, shortly thereafter, the output signal from the second passage detection mechanism is received, and the reception time of both signals is received. The interval is detected by a predetermined time unit. The first and second rotating bodies are driven when the drive shaft is driven in a no-load state in which the rotor is not immersed in the liquid to be measured. It is arranged that the passage of any one index of the first rotating body and the passage of any one index of the second rotating body are detected simultaneously by the two passing detecting mechanisms. Characteristic rotary viscometer. 3. The first rotating body according to claim 2, wherein the first rotating body is a first disk penetratingly fixed to the drive shaft and provided with an index at a position obtained by equally dividing the entire circumference into a plurality. The second rotating body penetrates and is fixed to the torque detection shaft,
A rotary viscometer characterized in that it is a second disk having the same number of divisions as the first disk and provided with indices at positions obtained by equally dividing the entire circumference into a plurality. 4. The apparatus according to claim 3, wherein the time difference detecting means comprises: a clock circuit for continuously transmitting a clock pulse having a predetermined transmission frequency; and the first passage detection mechanism comprising: Immediately after receiving the signal that has detected the passage of any one of the indices, the second passage detection mechanism receives the signal that has detected the passage of any one of the indices of the second disk. A gate circuit that inputs a clock pulse generated by the clock circuit and outputs it as it is; a counter that counts clock pulses output from the gate circuit to obtain the time difference between the two signals from both passage detection mechanisms. A rotary viscometer comprising: 5. The method according to claim 4, wherein the rotation drive source is a pulse motor, and the oscillation frequency of the clock circuit is obtained by multiplying a rotation speed of the rotation drive source by a predetermined constant. Characteristic rotary viscometer. 6. The first and second passage detection according to claim 5, wherein the indices provided on the first and second disks are slits for transmitting light formed on the disks. Each of the mechanisms has a light-emitting portion and a light-receiving portion, which are arranged so as to sandwich the corresponding disk from above and below, and the light-receiving portion of the passage detection mechanism has a light-emitting portion when the slit of the disk passes. A rotary viscometer, which receives an optical signal from the device and outputs a passage detection signal.